Aqueous systems have been widely used for home care and personal care applications by consumers or industrial users. Such aqueous systems, for example, aqueous fabric conditioning compositions, comprise large amount of water, and therefore, they require a great amount of packaging materials and large shelf space. Also, transportation of such aqueous systems is expensive. One solution to solve these problems is to provide solid systems for home care and personal care applications, such as solid fabric conditioning compositions.
Referring to fabric conditioning compositions, such compositions generally comprise one or more fabric conditioning actives. One widely used fabric conditioning active is quaternary ammonium compound which generally comprise long chain alkyl groups connected to the nitrogen atom. Quaternary ammonium compounds are known to impart fabrics “softness”. One significant improvement in the fabric conditioning field is to use quaternary ammonium compound with at least one ester functional group inserted in some or all of the long chain alkyl groups. Such quaternary ammonium compounds are called “ester quaternary ammonium compounds” or “ester quats”. One advantage of ester quats is that they are rapidly biodegradable, thus more eco-friendly. Use of ester quats for fabric conditioning compositions has been described, e.g. in U.S. Pat. No. 4,808,321 issued on Feb. 28, 1989; U.S. Pat. No. 5,066,414 issued on Nov. 19, 1991; U.S. Pat. No. 5,531,910 issued on Jul. 2, 1996.
Another development in the fabric conditioning field is addition of cationic polymers to the fabric conditioning compositions for various benefits. Useful cationic polymers include cationic polysaccharide. Such use of the cationic polysaccharides has been described, e.g. in U.S. Pat. No. 4,237,016 issued on Dec. 2, 1980, U.S. Pat. No. 6,492,322 issued on Dec. 10, 2002.
There are certain problems associated with known fabric conditioning systems comprising ester quats and cationic polysaccharides. For example, ester quats are susceptible to degradation, especially when they are present in high concentrations in water. This phenomenon may be due to their biodegradable nature. Furthermore, when quats coexist with polysaccharides, such as cationic polysaccharides, in a liquid system, the system is usually unstable. In particular, the quat component and the polysaccharide component tend to undergo phase separation.
There is a need to provide stable compositions which incorporate quaternary ammonium compounds and polysaccharides, especially stable compositions incorporate quaternary ammonium compounds and polysaccharides at high concentrations.